Soy Reduction

author: Helen Rennie source:


  • 10 fl. oz. bottle tamari style soy sauce(300ml / 360g)

  • 300g sake (1 and 1/4 cup)

  • 85g sugar (1/3 cup + 1 Tbsp)

  • 5g kombu (about 20 square inches)

  • 15g dry shiitake mushrooms (a handful)

  • 10g bonito (a big handful)


  • Combine all ingredients in a pot and bring to a simmer. Cook gently for 10 min.

  • Take off heat, cover, and let sit for 1 hour (or longer).

  • Strain into a non-stick skillet through a fine mesh sieve pressing firmly on the solids.

  • Boil down to a syrup (see the video for how to test if it’s reduced enough).

  • Cool slightly. Move to a glass measuring cup while still hot.

  • You should have roughly 2/3 cup sauce (there might be some foam above 2/3 cup line). If you ended up with less, stir in enough water to get to 2/3 cup. Otherwise the sauce will be too thick after cooling.

  • Cool to room temperature. Pour into a squeeze bottle.

  • Cover the top with plastic wrap and refrigerate overnight before use. Can be stored in the fridge indefinitely.